Rewinding mechanism for clock springs



Dec. 10, 1963 s. KOPLAR ETAL 3,113,639

REWINDING MECHANISM FOR CLOCK SPRINGS Filed 001;. 30, 1961 i I 20 a JNVENTOR5" 72/5? flrraxmars.

United States Patent 3,113,639 REWINDING MECHANISM FOR CLOCK SPRINGS Solomon E. Koplar and Ignacio R. Quiroz, Chicago, Ill., assignors to Rubber Products, Inc., Chicago, 111., a corporation of Illinois Filed Oct. 30, 1961, 8 No. 148,606 1 Claim. (Cl. 185-40) This invention relates to new and useful improvements in a rewindingmechanism for clock springs and more particularly to a means for intermittently energizing a battery-powered motor through a novel switch arrangemerit for rewin'ding the power spring of the clock mechanism.

A principal object of o'ur'invention is the provision in a mechanism of this character of an arrangement of parts whereby a battery-powered motor will be intermittently energized through a switch arrangement which is actuated by the unwinding of the clock power spring, which switch action will cause the motor to be rendered inoperative after the power spring has been rewound to a predetermined tension.

A further object of our invention is the provision in a mechanism of this character of a novel switch mechanism for intermittently energizing the battery-powered motor.

Yet another object of our invention is the provision in a mechanism of this character of an arrangement of parts which will prevent the power spring from completely unwinding upon the failure of the battery-powered motor to perform its function of maintaining the tension of the spring between specific predetermined degrees.

An equally important object of our invention is the provision in a mechanism of this character of an arrangement of parts which is simple in construction, economical in manufacture, and which produces a clock mechanism which operates reliably and accurately.

Other objects will appear hereinafter.

The invention consists in the novel combination and arrangement of parts to be hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawings showing the preferred form of construction, and in which:

FIG. 1 is a fragmentary side elevational view showing our spring rewinding mechanism;

FIG. 2 is a fragmentary sectional detail view of our novel construction and switching arrangement;

FIG. 3 is a fragmentary explosive view showing certain parts of our invention.

In describing and illustrating our invention, reference will be omitted to the standard clock members such as the gear trains and associated parts that are well-known in the art and do not make up any portion of the present invention.

Extending through a back plate of a clock body is a minute hand shaft 11. This shaft has fixedly mounted thereon a cup-shaped disc 12. Contained within the circular periphery of this disc 12 is the clock power spring 13. This power spring 13 has one end inserted through a slot 14 formed in the periphery of the disc 12 and fixedly attached thereto as at 15. This power spring 13 is coiled about an elongated sleeve 16 into which the free end of the minute shaft 11 freely projects. The inner coiled end of the spring 13 is fixedly attached in any approved manner to the exterior surface of the sleeve 16.

The elongated sleeve 16 is a part of the bearing 17 upon which is fixedly mounted the gear wheel 18. A thrust collar 19 is mounted in a circular opening 20 formed in the face of the bearing 17 as seen in FIGS. 2 and 3, and acts as a free bearing for the end of the shaft 11.

Freely journaled on the sleeve 16 between the gear wheel 18 and the disc 12 is a contact drum 21. One face of this drum 21 is hollowed out as at 22 and, as such, provides one side cover for the disc 12 and coil spring 13 when they are mounted in operative position with respect to each other as seen in FIG. 2. Secured to a portion of the periphery of the contact drum 21 is a segment of insulating material 23, for purposes hereinafter made apparent.

The drum 21 has a drive pin 24 extending laterally therefrom in a plane parallel to the shaft 11 and in spaced relation to the periphery of the disc 12. Extending laterally from the opposite side of the drum 21 is a safety finger 25. This safety finger 2'5 freely projects through an arcuate slot 26 formed in the gear wheel 18-. The disc 12 is provided with a trip arm 27 extending from the peripheral edge thereof in a direction transversely to that of the drive pin 24 and is so arranged with respect thereto that during the rotation of the disc 12'- by the unwinding action of thepower spring 13, it' will engage and cause to move in the same direction the drive pin 24 and the contact drum 21.

Carried by a suitable bracket 28 mounted on the back plate 10 of the clock body are switch arms 29 which have their free ends 30 riding on the peripheral edge of the contact drum 21'. These switch arms 29 are connected by a conduit 31 to one side of abattery (not shown). The other side of the battery is connected through a conduit 32 to one side of an electric motor 33 in turn connected by conduit 34 to a commutator type connection (not shown) of the contact drum 21.

The motor 33 has a driven shaft 35 which in turn is provided with a worm type gear 36 which operatively meshes with the teeth of the gear wheel 18 as seen in FIG. 1.

In operation, the power spring 13 unwinds and causes the minute hand shaft 11 and the disc 12 to rotate in a clockwise direction as seen in FIG. 1. The switch arms 29 are normally at rest upon the segment of insulated material 23 carried by the contact drum 21. In the course of the clockwise rotation of the disc 12, the trip arm 27 will engage the drive pin 24 and cause the contact drum 21 to rotate in the direction of the arrow as seen in FIG. 1. The safety finger 25 will freely move in the slot 26 formed in the gear wheel 18. When the contact drum 21 is thus rotated at sufiicient distance, the segment of insulating material 23 will pass from beneath the ends 30 of the switch arms 29 and when the same engage the peripheral edge of the contact drum 21, the motor 33 will be energized, causing through the worm gear 36 the clockwise rotation of the gear wheel 18.

As the gear wheel 18 rotates, the end of the slot 26 will engage the safety finger 25 of the contact drum 21 and cause it to rotate in the same direction and at the same speed as the gear wheel 18. This rotation continues until the ends 30 of the switch arms 29 again ride upon the insulated segment 23, at which time the motor 33 is deenergized. The power spring 13 has in the meantime caused the disc 12 and the trip arm 27 to move to a position whereby it will be on the opposite side of the drive pin 24 as viewed in FIG. 2, and thus the disc 12 will be caused to rotatethrough a complete revolution before the trip arm 27 carried thereby again engages the drive pin 24.

In the event that the foregoing described operation takes place but the battery is dead, the disc 12 will rotate together with the contact drum 21 until the safety finger 25 reaches the end or lowermost portion of the slot 26 as viewed in FIG. 1. At this point, as the gear wheel 18 is held against rotation through the inactive motor 33, the clock will stop and the power spring 13 will not be permitted to completely unwind.

While we have illustrated and described the preferred form of construction for carrying our invention into effect,

this is capable of variation and modification without departing from the spirit of the invention. We, therefore, do not wish to be limited to the precise details of construction set forth, but desire to avail ourselves of such variations and modifications as come within the scope of the appended claim.

Having thus described our invention, what we claim as new and desire to protect by Letters Patent is:

A rewind mechanism for a clock power spring including (a) a spring driven shaft,

(b) a spring housing disc mounted on and rotatable with said shaft,

() an elongated sleeve freely journaled on said shaft and extending inwardly of said housing disc,

(d) a coiled power spring having one end connected to said sleeve and the other end connected to said disc for rotating said disc and said shaft in one direction as it unwinds,

(e) a battery powered electric motor having an energizing circuit for rewinding said spring,

(f) a gear wheel freely journaled on said sleeve and rotatable in one direction by said motor for rewinding said spring,

(g) a contact drum connected in circuit to the battery of said motor and freely rotatable on said sleeve between said gear wheel and said housing disc,

(/1) a switch in the circuit to said motor adapted to engage said drum to complete the circuit for energizing said motor,

(1') means on said drum for preventing said switch from engaging said drum so as to complete the circuit to said motor,

(j) a trip arm on said disc for engaging said drum as it is rotated by said spring so as to initially rotate said drum in one direction about said sleeve and independently of said gear wheel so as to cause said preventing means to become ineffective to prevent said switch from engaging said drum to complete the circuit so as to energize said motor,

(k) said motor upon being energized rotating said gear wheel and said sleeve upon said shaft in said one direction for a predetermined period of time so as to rewind said power spring,

(I) said gear wheel having formed therein a slot through which projects a pin carried by said drum,

(m) said pin freely movable through said slot when said drum is initially rotated by said disc without imparting corresponding movement to said gear wheel or said sleeve,

(11) upon energization of the motor said gear wheel being rotated by said motor in said one direction will have one end of said slot engage said pin so as to cause continuous rotation of said contact drum with said gear wheel by said motor independently of rotation of said disc.

References Cited in the file of this patent UNITED STATES PATENTS 1,806,969 Fowler May 26, 1931 

